APBio topics 6.5-6.6 Review Part 2

A protein that binds to the operator and blocks the RNA polymerase

• regulator
• repressor
• activator
• corepressor

The "on/off" switch for an operon is called the

• promoter
• repressor
• operator
• gene

What is the name of the stretch of DNA where RNA polymerase binds?

• operator
• promoter
• enhancer
• origin

What is the role of operons in prokaryote gene expression?

• It makes the genes prokaryotes be turned on
• It accounts for the regulation of gene activity in response to the needs of the cells
• To make DNA for the gene
• To make the gene turn of and off

Inducible negative control is when when the gene is transcribed by the ____ of a specific molecule

• presence
• absence

Repressible negative control is when when the gene is transcribed by the ____ of a specific molecule

• presence
• absence

What type of operon is the trp (tryptophan) operon?

• inducible
• repressible
• positive control
• promoible

The regulation of an operon by repressor is referred to as

• negative regulation

• positive regulation

• both a and b

• neutral regulation